Tubular body



March 21, 1944. E, c;` CROWLEY 2,344,538

TUBULAR BODY Filed Feb. 7, 1942 Patented Mar.421, 1944 UNITED STATES PATENT OFFICE TUBUIAR BODY Edward Chase Crowley, Rh-inebeck, N. Y.

Application February 7, 1942, Serial No. 429,861

8 Claims.

This invention relates to a new type tubular article having alternating plane sides and curved corners, and formed from a strip of metal helically wound upon itself, with the adjacent edges of the strip interlocked to form a continuous tubular article with an interlocked seam and reinforced construction.

Other features of the invention relate to tubular bodies with a new and improved type of seam affording greater strength to the interlocked edges of the strips and to end closures and supports therefor.

The above and other objectives will be fully understood from the following description of the invention when considered in connection with the drawing, wherein Figs. 1 to 4 are diagrammatic cross sectional views through tubular articles made in accordance with my invention and illustrating respectively the square, rectangular, triangular, and oblong form in which such tubes may be made.

Fig. 5 is an enlarged sectional view illustrating my improved seam.

Fig. 6 is an elevational view of a container formed in accordance with my invention.

Fig. 'I is an end view thereof.

but of rectangular form. having two longer and two shorter sides.

Fig. 3 illustrates a similar article I2 of triangular form, and Fig. 4 illustrates the tubular article I3 with two fiat sides and two curved ends.

Referring to Fig. 5, the seam I6 there illustrated is formed inside the plane of the material I4 constituting the main body of the article. It will be understood that the seam may be either on the inside or on the outside, depending upon the particular use to which the tubular article is to be put. The seam is formed of a reverse bend I1 on one edge of the strip and a similar reverse bend I8 at the opposite edge of the adjacent strip. The extension or flange I8 is formed as a continuation of the flange I9 pressed inwardly as at 2D from the main body of the strip constituting the side wall I4. This type of seam is formed by said method by passing the edges of the strips through pre-forming rolls to score and bend the f adjacent edges into form and position to be in- Fig. 8 is a sectional view of one of the end l closures of the container illustrated in Figs. 6 and 1, taken substantially on the line 8 8 of Fig. 7.

Figs. 9 and 10 are detailed perspective views of end reinforcing members employed in the formation of the end closures.

The tubular article herein disclosed can be formed on the apparatus and by the method shown and described in my copending United States patent application Ser. No. 350,640, filed August 3, 1940, of which the present application is a continuation in part. The improved and sealed lock-seam can be formed on the aforesaid apparatus and by the aforesaid method when applied to the tubular articles herein disclosed or by the aforesaid method with other suitable apparatus when applied to round tubes or other articles.

Referring to the details of the drawing,

Fig. 1 illustrates a tubular article I0 of square formation and wherein the four plane sides are joined by four curved corners. the article being made of a spirally wrapped strip of metal, as shown in Fig. 6, and preferably embodying the seam illustrated in detail in Fig. 5.

Fig. 2 illustrates a similar tubular article II,

terlocked and compressed by seaming rolls into the form illustrated whereby they form a subf stantially integral mass.

I have found that by placing longitudinal grooves or score marks 22 on the two contacting faces of the inner extensions of the seam, and with the scores and bent edges formed specifical- 'ly for interlocking engagement a seal may be tinuous seam, by the union and consolidation i of said scored edges, extending throughout the interior of the helical seam.' Obviously such grooves and complemental ridges may be increased in number over those shown. in said Fig. 5 and disposed at other or additional points within the interior of `said lockseam, such as the lpoints above and below the grooves and complemental ridges shown in the center of said Fig. 5.

Referring to Fig. 6. the tubular body 24 is formed of the spirally wound and interlocked strips described above. A desirable form of end vclosure is shown, the closure to be applied to one or .both ends of the body, as desired. As illus- 65 trated, the closure may comprise a reinforcing and connecting element 25 of the "s'ame shape as the container, square in the illustration of Figs. 6 to 8, the element being formed from a tapered strip of metal such that its minimum height corresponds tothe distance from the last convolution of the spiral seam to the edge of the container and its meeting point may be as desired. The thickness of the strip 25 may desirably be the same as the thickness of the seam when it projects from the plane of the container wall.

The closure membrane 26 is preferably dished from the container wall to the bung 28 and formed with a flanged portion 29 which may have a bend 30 therein entirely surrounding the closure and resting upon the end of the container and reinforcing ring 25. The bung 28 may be formed as a casting or stamping 32, soldered or welded in an opening at the center or toward a corner of the closure membrane and constructed to receive a screw-threaded or otherwise removable plug 33.

The end of the container is preferably further reinforced by the elevated or raised radiating strips 34 and 36, the strips 34 being relatively shorter and preferably extending from the bung tothe center of each side edge, the strips 38 extending from the bung to each of the four corners. As shown, the strips 34 are of general U- formation, with the vertical flanges or sidewalls 31 extending from the closure membrane to the web of the U, the outer surface of the latter being positioned generally in the plane constituting the end of the assembled container. end of the reinforcing strips 34 adjacent the bung 28 may be cut away to avoid interference with the plug 33. The outer ends may be formed with wings 38 for attachment against the flanged portion 29 of the closure membrane and with an extension 39 extending across the reinforcing ring and end of the container.

form adapted to greater usefulnesf. than other types of containers. For example. with containers formed of the cross sectional form illustrated in Figs. 1 to 4. such containers can be stacked one against the other with substantially no lost space as prevails at the present time with round containers. Conduits formed with plane sides and curved corners are many times usable in places where a round conduit wouldvnot serve.

The tubular form shown in Fig. 4 is particularly useful asa slab for building materials and the like. either filled with some other material or empty.

In all cases the tubular article is of great strength for the thickness of metal employed owing to the reinforcing effect of the continuous sealed spiral rib herein disclosed. It will be noted from Figs. 1-8 that the familiar rib or truss formed by the folded and projecting layers of material in the seams is disposed in substantially rectilinear form instead of the conventional round form. Said figures show that the respective, continuous seams have all been bent into series of straight struts disposed on the plane surfaces and alternating series of curved struts disposed on the curved surfaces; and that said respective straight and curved truss-forming por- The inner The reinforcing strips 36 are similar to 34 except that at the corners they are preferably extended to provide downwardly extending flanges 4U to overlie the outer edge of the corners. 'Ihe webs of all of said strips 34 and 36 are disposed in the same plane and these webs present in radial formation a grid bearing surface for end stacking of such tubular bodies. It will be understood that the strips 34 and 36 may be of channel form, as shown, or in the form of a T or angle with 4the webs in a plane surface, as

shown, or in the form of raised corrugations in said closure membrane for such reinforcement and end stacking.

In assembling the end closures, each of the parts 'constituting the closure membrane, the bung, the reinforcing ring, and the reinforcing strips may be formed as illustrated. The element 25 is set in position and the bung 28 is soldered or welded in the opening in the closure membrane. The membrane then may be set in place and the flange 29 welded or brazed in position tions of the continuous seam are connected at their respective ends and angularly disposed with respect to each other to form the aforesaid continuous truss. It has been found unnecessary to weld or otherwise additionally seal the joints formed as illustrated in Fig. 5, a common practice with other types of seam.

Having now described my invention, I claim:

1. An article of manufacture comprising a tubular body portion and an end closure therefor, said tubular body portion being formed of strip metal spirally wound and secured at the edges thereof in a spiral interlocked seam, said end closure comprising a closure membrane having a flange disposed about the periphery thereof andan exterior reinforcing member positioned outwardly of said membrane and formed with a web spaced outwardly from said membrane and positioned in a plane perpendicular to the axis of the tubular structure and with a flange extending inwardly to said membrane, said reinforcing member being secured at an end thereof to the said flange of said membrane, said end closure including also an interior reinforcing band extending around the interior of the end of said tubular body portion and of a variable height corresponding to the distance between the last convolution of the seam and the end of the tubular body.

. 2. An article of manufacture comprising a tubular body portion and an end closure therefor, said tubular body portion being formed of strip metal spirally wound and secured at the edges thereof in a spiral interlocked seam, said end closurecomprising a closure membrane and an interior reinforcing band extending around the interior of the end of said tubular body portion and of a variable height corresponding to the distance between theV last convolution of the seam and the end ofthe tubular body. V

3. As a new article of manufacture. a tubular structure composed of strip metal helically wound upon itself in a series of continuous convolutions with their adjacent edges `joined and lar articles as herein disclosed are of particular locked in a continuous helical seam composed of a plurality of layers of said strip metal and having alternating curved surfaces and plane surfaces defining its cross sectional dimensions, said seam constituting a continuous integral reinforcing truss on said structure in an alternating series of straight struts disposed on said plane surfaces and curved struts disposed on said curved surfaces. y

4. As a new article of manufacture, a tubular structure composed of strip metal helically wound upon itself in a series of continuous convolutions with their adjacent edges joined and locked in a continuous helical seam composed of a. plurality of layers of said strip metal and having alternating curved surfaces and plane surfaces detlning its cross sectional dimensions, said y structure being of generally rectangular form in cross section, said seam constituting a continuous integral reinforcing truss on said structure in an alternating series of straight struts disposed on said plane surfaces and curved struts disposed on said curved surfaces.

5. As a new article of manufacture, a tubular structure composed ofv strip metal helically wound upon itself in aseries of continuous convolutions with their adjacent edgesjoined and locked in a continuous helical seam composed of a plurality of layers of said strip metal and having alternating curved surfaces and plane surfaces defining its cross sectional dimensions, said structure being of generally triangular form in cross section, said seam constituting a continuous integral reinforcing truss on said structure in an alternating series of straight struts disposed on said plane surfaces and curved struts disposed on said curved surfaces.

6. As a new article of manufacture, a tubular structure composed of strip metal helically wound upon itself in a series of continuous convolutions with their adjacent edges joined and locked in a continuous helical seam composed of a plurality of layers of said strip metal and having alternating curved surfaces and plane surfaces dening its cross sectional dimensions, said structure having two opposed flat sides and two opposed curved ends in the cross sectional dimension thereof, said seam constituting a continuous integral reinforcing truss on said structure in an alternating series of straight struts disposed on said plane surfaces and curved struts disposed on said curved surfaces.

7. An article of manufacture comprising a tubularbody portion and an end closure therefor, said tubular body portion being formed of sti-ip metal spirally wound in a series of convolutions and secured at the edges thereof in a. spiral interlocked seam in spiral ribbed formation and said end closure comprising a closure membrane and a reinforcing band extending around the end of said tubular body portion and of a variable height corresponding to the distance between the last convolution of the seam and the end of the tubular body.

8. In a spiral, tubular construction a lock seam joint composed of the bent-over edges of two convolutions of strip material having scoring on the opposite faces of said edges at the extremities thereof, said scored extremities being disposed in the central portion of said lock seam joint and united to provide` a substantially intcgral mass extending longitudinally throughout said central portion, and 'disposed to fill and completely close the said central portion of said joint, and to form an interior seal for said joint.

EDWARD CHASE CROWLEY. 

